Section 15: Rules applicable to substance of dispute

(1) The arbitral tribunal shall decide the disputes in accordance with the rules of law that is chosen by the parties as applicable to the substance of the dispute.
(2) Any designation of the law or legal system of a given jurisdiction or territory shall be construed, unless otherwise expressed, as directly referring to the substantive law of that jurisdiction or territory and not to its conflict of law rules.
(3) Where parties fail to choose or designate any law or legal system of a given jurisdiction or territory as required in subsection (1), the arbitral tribunal shall apply the law determined by the conflict of law rules which it considers applicable.
(4) The arbitral tribunal shall not decide ex aequo et bono or as amiable compositeur, unless the parties have expressly authorised it to do so.
(5) In all cases, the arbitral tribunal shall -
(a) decide in accordance with the terms of the contract; and
(b) where established by credible evidence, take account of the usages of the trade applicable to the transaction.